1. Field of the Invention
The present invention relates to an alert system installed in a vehicle which is preferably applied to an alert device that issues an alert to a driver when dozing at wheel or deviation from the lane is detected in order to draw the attention of the driver.
2. Description of the Related Art
Conventionally, there has been proposed an alert system (see Japanese Patent Application Laid-Open No. 2002-46542) for acquiring an image ahead of the vehicle by a camera, calculating a lateral position (lateral deviation with respect to the lane) of the vehicle from the result of image processing such as road lane recognition, deriving the degree of less alertness of the driver and the possibility of lane deviation from vehicle speed, steering wheel angle, accelerator depression amount, brake pedal on-off state, cultch operation state, transmission shift position, and flasher lever operation state, and issuing an alert through a speaker or a monitor to the driver in accordance with the result of the deriving.
However, a conventional system is formed by three main devices of a camera, a controller (ECU) and an alert issuing device (a speaker or a monitor). Therefore, it has been difficult to install these devices in a vehicle which is not equipped with an alert system afterwards to realize an alert system.
With the foregoing problem in view, the object of the present invention is to provide an alert system that can be installed in a vehicle with ease.